Linux Kernel up to 5.6 SELinux Subsystem ebitmap_netlbl_import null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Linux Kernel up to 5.6. This affects the function ebitmap_netlbl_import of the component SELinux Subsystem. Executing a manipulation can lead to null pointer dereference. This vulnerability appears as CVE-2020-10711. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 5.6 (Operating System). This vulnerability affects the function ebitmap_netlbl_import of the component SELinux Subsystem. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem in versions before 5.7. This flaw occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the system kernel, resulting in a denial of service.

The weakness was presented 05/22/2020 as not defined bug report (Bugzilla). The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2020-10711 since 03/20/2020. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 208643 (CentOS 7 : kernel-alt (RHSA-2020:2104)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.7 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (208643). Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 208643
Nessus Name: CentOS 7 : kernel-alt (RHSA-2020:2104)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.7

Timelineinfo

03/20/2020 🔍
05/22/2020 +63 days 🔍
05/22/2020 +0 days 🔍
10/12/2024 +1604 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: bugzilla.redhat.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2020-10711 (🔍)
GCVE (CVE): GCVE-0-2020-10711
GCVE (VulDB): GCVE-100-155548

Entryinfo

Created: 05/22/2020 19:28
Updated: 10/12/2024 05:18
Changes: 05/22/2020 19:28 (42), 05/22/2020 19:33 (12), 10/19/2020 07:37 (1), 10/19/2020 07:45 (1), 10/12/2024 05:18 (17)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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